Officially Islamic Republic of Iran, republic (2005 est. pop. 68,018,000), 636,290 sq mi (1,648,000 sq km), SW Asia. The country's name was changed from Persia to Iran in 1935. Iran is bordered on the north by Armenia, Azerbaijan, Turkmenistan, and the Caspian Sea; on the east by Afghanistan and Pakistan; on the south by the Persian Gulf and the Gulf of Oman; and on the west by Turkey and Iraq.